1. Environmental Engineering Department, Faculty of Engineering and Architecture; Abant Izzet Baysal University; Bolu Turkey
2. NOAA Earth System Research Laboratory, Chemical Sciences Division; Boulder Colorado USA
3. Cooperative Institute for Research in Environmental Sciences; University of Colorado; Boulder Colorado USA
4. Now at Department of Environmental Sciences; University of California; Riverside California USA
5. Now at Department of Chemistry; Memorial University of Newfoundland; Newfoundland Canada
6. Department of Chemistry and Biochemistry; University of Colorado; Boulder Colorado USA